std::unique_copy
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<tbody> </tbody>| Elemento definito nell'header <algorithm>
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template< class InputIt, class OutputIt > ForwardIt unique_copy( InputIt first, InputIt last, OutputIt d_first ); |
(1) | |
template< class InputIt, class OutputIt, class BinaryPredicate > ForwardIt unique_copy( InputIt first, InputIt last, OutputIt d_first, BinaryPredicate p ); |
(2) | |
Copia gli elementi dal
[first, last) gamma, ad un altro inizio intervallo su d_first in modo tale che non vi siano elementi consecutivi uguali. Solo il primo elemento di ciascun gruppo di elementi uguali viene copiato. La prima versione utilizza operator== di confrontare gli elementi, la seconda versione utilizza il predicato binario dato p.Original:
Copies the elements from the range
[first, last), to another range beginning at d_first in such a way that there are no consecutive equal elements. Only the first element of each group of equal elements is copied. The first version uses operator== to compare the elements, the second version uses the given binary predicate p.The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
Parametri
| first, last | - | l'intervallo di elementi di processo
Original: the range of elements to process The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
| d_first | - | l'inizio del campo di destinazione
Original: the beginning of the destination range The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
| p | - | binary predicate which returns true if the elements should be treated as equal. The signature of the predicate function should be equivalent to the following:
The signature does not need to have |
| Type requirements | ||
-InputIt must meet the requirements of InputIterator.
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-OutputIt must meet the requirements of OutputIterator.
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-The type of dereferenced InputIt must meet the requirements of CopyAssignable.
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-The type of dereferenced InputIt must meet the requirements of CopyConstructible. if neither InputIt nor OutputIt satisfies ForwardIterator
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Valore di ritorno
Uscita iteratore all'elemento passato l'ultimo elemento scritto
Original:
Output iterator to the element past the last written element
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
Possibile implementazione
| First version |
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template<class ForwardIt, class OutputIt>
ForwardIt unique_copy(ForwardIt first, ForwardIt last,
OutputIt d_first)
{
if (first == last)
return d_first;
*d_first = *first;
while (++first != last) {
if (!(*d_first == *first)) {
*(++d_first) = *first;
}
}
return ++d_first;
}
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| Second version |
template<class ForwardIt, class OutputIt, class BinaryPredicate>
ForwardIt unique_copy(ForwardIt first, ForwardIt last,
OutputIt d_first, BinaryPredicate p)
{
if (first == last)
return d_first;
*d_first = *first;
while (++first != last) {
if (!p(*result, *first)) {
*(++d_first) = *first;
}
}
return ++d_first;
}
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Esempio
Le finiture del programma seguenti tutti gli spazi multipli consecutivi in una stringa const e stampa il risultato
Original:
The following program trims all multiple consecutive spaces in a const string and prints the result
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
#include <string>
#include <iostream>
#include <algorithm>
#include <iterator>
int main()
{
std::string s1 = "The string with many spaces!";
std::cout << "before: " << s1 << '\n';
std::string s2;
std::unique_copy(s1.begin(), s1.end(), std::back_inserter(s2),
[](char c1, char c2){ return c1 == ' ' && c2 == ' '; });
std::cout << "after: " << s2 << '\n';
}
Output:
before: The string with many spaces!
after: The string with many spaces!
Complessità
lineare la distanza tra
first e lastOriginal:
linear in the distance between
first and lastThe text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
Vedi anche
trova due identici (o qualche altra relazione) elementi adiacenti l'uno all'altro Original: finds two identical (or some other relationship) items adjacent to each other The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (funzione di modello) | |
| removes consecutive duplicate elements in a range (funzione di modello) | |